Through Darkness And Light We Will Unite
by SugoiMasta'69
Summary: After dying in his battle against Arima in the sewers, Kaneki was reborn in another world as the son of All For One. In a world where quirks and superheroes were a natural thing, he found himself becoming what he hated the most. Sent undercover as a hero in training by his father, he met a girl who may be able to change his heart. [Fem!Deku X Manga!Kaneki]
1. Prologue - The Birth Of Darkness

**AU NOTE:** **So I've been watching and reading a lot of BnH lately. Thought this concept might be fun to experiment with. Feel free to ask me anything.**

* * *

 _Ah, I'm dead, aren't I?_ Kaneki thought, sadness clear in his bitter thoughts. Yet, he felt an odd sense of happiness. _I did it, I finally died in style._ If he could smile, he would have.

As Kaneki prepared to faint into darkness, voices slowly surrounded him and got louder by the second. He couldn't comprehend why he could still hear and neither could he understand what they were saying. This went on for what seemed to him like an eternity. He couldn't make sense of what they were trying to say, as his mind felt numb.

"So you've finally arrived."

Surprised to hear a voice so clearly, he felt his body move around - as if he was being handed over to someone. Already knowing what was occurring, he opened his eyes. The light nearly blinded him but was covered by a tall figure that stood in front of him. Rather, the figure was holding him tightly as if he was a baby. Looking up, he saw a man's face covered by scar tissue except for the mouth. Several tubes and medicinal stuff were connected to him. On the man's lips, a wicked grin was placed.

"My invaluable pawn."

This marked the day that Kaneki Ken was reborn. Born into the world where evil and good clashed against each other every day through the help of superpowers. And his supposed father just so happened to be the greatest evil of this world.


	2. Chapter 1 - All For One

**AU Note:** **I was unaware as to when All For One's battle against All Might happened, so I just changed it so their fight was before All Might's debut as a pro hero. Will probably change it if I find out I messed up or something.**

 **Anyways, Kaneki may feel a bit OOC if you're not caught up with the manga (just a reminder that this is Manga Kaneki. To be more precise, it's pre-haise but post-aogiri Kaneki).**

 **Guest: You my good sir are a genius**

 **Me: Not really, but thanks I guess. As said, I'm experimenting a lot so I might fuck up xD**

 **Sandwich: Question will kaneki eventually get his villain side? Maybe even backstabbing them but that is just me**

 **Me: This chapter should make it clear. Although, I don't plan on making the road or end goal as predictable as it might seem.**

 **Angryboy13: All right quick question, will any of these scenes happen?**

 **Me: Yes lmfao on point as fuck. Probably in a more serious take, but yes.**

* * *

Four years passed by and Kaneki understood the situation he was in. Reborn into a world of superheroes, he accepted the new opportunity that fate had offered him. After all, he had completed his part of his goal in his previous life, so if he could complete the other in this world - he could die without regrets.

In the short four years that he had experienced life in this new world, he learned a few things.

His name was the same as before, Kaneki Ken. The name was given to him by his father, as his mother was declared dead after giving birth.

Despite knowing how his father looked like, he never knew his name. In fact, all he could remember about his father was what he first thought to be mad ramblings. But after sneaking around the house and eavesdropping one of his conversations, he learned that his father was actually talking with others through a machine.

"Yes, bring him to me. His quirk will surely be of use to us."

Kaneki stood in silence by the doorframe and peaked into the room, not knowing what his father meant. After sighing briefly, he felt a deadly presence and looked up with dread. In front of him stood his father. Not knowing whether he was glaring at him or not due to the scar tissue covering his face, Kaneki couldn't help but gulp in fear.

"F, father…." Kaneki stuttered, feeling the killing intent leak out of his father.

"Hmm, it seems that you're still quite soft. If this amount is enough then I might as well dispose of you." His father said disappointedly, letting his killing intent disappear.

"I'm not soft," Kaneki said with a pout, furrowing his eyebrows. "You're just too strong, Father."

"Yes, I suppose that might be the case." His father chuckled and went inside the room. "Come, I must show you something my dear pawn."

Kaneki was used to this treatment but still obeyed diligently. He didn't have the courage to oppose him or flee as if he chose either then he would surely die without accomplishing the rest of his goal. His father, from what Kaneki heard, was supposed to be the leader of a villain organization.

"Yes, father," Kaneki said as he walked inside and closed the door behind him. He watched silently, as his father sat on the office chair and brought a video on the computer screen.

On the screen, one could see All might ascend from the collapsed truck, as he held onto several injured civilians. On the background, one could see several collapsed and burning buildings.

"Did you see that?! He has already saved 100 people! And it didn't even take 10 minutes! Really, what a monster!"

"He laughs loudly!"

As Kaneki watched the footage, he looked briefly over to his father.

"No, look. You must look. This is a great opportunity for your growth." His father said and he obeyed.

As All Might stood on top of the truck and laughed, he shouted the following words.

"You no longer have to worry! Why do you ask? Because I am here!"

A glimpse of admiration sparkled on Kaneki's eyes, reminding him of the things he couldn't accomplish. To be loved by everyone and then die in style.

 _A good or a bad thing, it doesn't matter… And after that, I'll die in style..._ As Kaneki thought that, he began to chuckle darkly. A wicked grin was placed on his lips and he looked down, making his hair overshadow his eyes. His father watched him with peaked interest, not quite understanding Kaneki's behavior but still finding it delightful. _Becoming a top hero or top villain, it doesn't matter…. Both will make me be able to die in style, right?_

"Hmm, I expected you to look at him with admiration or happiness, but this reaction… Oh yes, it's certainly most exciting." His father said, a grin placed on his lips. "Kaneki Ken." As he said his son's full name, said person looked up at him with a crazed smile.

"Don't worry father, I'll be sure to surpass you -" Kaneki said, fully accepting the options that this world had given him. Perhaps if he had been born into a hero's family things would have been different, but now all that mattered was accomplishing his goal one way or the other. And currently, the villain's side just so seemed to be the more favorable one. "I'll become the greatest evil this world has seen."

Thus, Kaneki Ken had made his mind up to accomplish his goal - even if it meant becoming what he had hated the most.

* * *

Ever since then, Kaneki trained his new body to achieve his max potential. He had even acquired his quirk, which he called "Binge Eating". The quirk allowed him to regenerate and heal any part of his body in an instant, plus it granted him superhuman strength. At first, the quirk was weak, could barely heal a scratch and granted him minimal strength. But eventually, he discovered that it kept growing stronger with the more calories he consumed. He wondered what would happen if he ate human flesh.

Currently, Kaneki was doing push ups in his father's training room. As his body neared the ground, he took a bite of meat that was placed on a plate below his face. For his age of only 15 years old, he physique was incredible. Perhaps, it was even better than what it had been in his past life.

"Kaneki." He heard his father's voice by the door and stopped doing pushups. Kaneki stood up and grabbed his plate in the process, as he head over to open the door. Munching on the greasy meat on his plate, he opened the door and saw his father stand in front of him.

"Yes?" Kaneki asked, placing his empty plate on a table beside them.

"Do you remember what we spoke about a month ago?" His father asked sternly.

"This again? Look, I already told you that I'm not going to play being a hero." Kaneki said, narrowing his eyes at his father. He felt the killing intent of his father but simply rolled his eyes.

"Hmm, it would seem that you can handle that much already. However, that does not matter." His father shook his head with a smile. "The matter at hand is that if you wish to surpass me, then this is an important task that you must complete."

"But -"

"Unless you wish for Shigaraki Tomura to be my successor instead?"

Kaneki stood in silence and eventually sighed.

"Fine." He said.

"Good, you'll be attending Yueei's entrance exam in a week," His father said, as he turned his back towards Kaneki and left through the dark hallways. "I expect lots from you, my dear pawn."

"..." Kaneki stared at his back in silence, unknowing that this was the turning point of his new life.


	3. Chapter 2 - Darkness Meets Light

**AU NOTE:** **Again I'm experimenting, so sorry if I fuck anything up. I'm trying to stay true to the characters, but honestly, it's rather fucking hard. Although, it does seem reasonable that Kaneki would change after spending 15 years in a brand new world. Anyways, hope this is to your liking. Don't expect chapters to come out this frequent tho, since I'm starting studying tomorrow.**

* * *

Kaneki stood by the entrance of Yuuei Academy. He looked down at his smartphone with a frown, before turning it off. He looked around him and inspected the other examinee's, who unlike him wore normal clothes.

Kaneki wore a pair of black sneakers and a battle suit that tightly embraced his body. Above it, he wore a pair of black shorts and a black sleeveless hoodie. As for his face, he looked like a younger version of himself before he died with the exception of having black hair and not having black fingernails.

"What's up with that kid, he's wearing all black…"

"Scary…"

Kaneki smiled at hearing the murmurs from around him and put his hood over his head. He entered the school and searched for a way to the place where the exam would be taking place. On his way, he stumbled upon a person.

Kaneki looked down at said person and that it was a girl around his age. Her hair was green, curly and reached to her shoulders.

"S- sorry!" Izuku said, even though she was the one to fall on the floor.

Kaneki stared at her in silence, before blinking and apologizing. "It seems like I was spacing out, I'm sorry about that!" Kaneki grinned with closed eyes and cupped his chin with his right hand.

"U- um, it's fine…! I… I was spacing out as well…." Izuku giggled nervously as she scratched the back of her head in embarrassment. Her cheeks were bright red and she was flustered.

"If you say so…" Kaneki sighed and reached out to her with a hand. Izuku accepted the gesture hesitantly with a shaking hand and stood up. She dusted her skirt off and spoke up.

"So, um, it's nice to meet you…." She spoke with stammers and trailed off, when she realized that she didn't know the boy's name.

"Kaneki Ken," Kaneki said with a smile.

"I'm Midoriya Izuku, it's nice to meet you Kaneki-san!" Izuku said excitedly, feeling her heartbeat rise as she thought she had embarrassed herself - feeling she was to outgoing. Nevertheless, she held a grin up and tried to hide her flustering.

"It's a pleasure to meet you Midoriya-san," Kaneki said, cupping his chin with his hand. As he said so, they heard the announcement that the entrance exam briefing would be starting soon. As they heard so, they turned to each other.

"We better hurry," Kaneki said.

"Y- yeah!"

They both hurried over to the briefing site, although Kaneki soon noticed that Izuku was not behind him. After looking behind, he saw that she was floating in the air and spoke with a brown-haired girl beside her. Kaneki simply sighed and went on to the briefing site. After finding a seat at the site, Kaneki listened carefully to the presentation.

"Welcome everyone to my live show!" Kaneki recognized the person talking as Present Mic, which made him frown. Present Mic was way too obnoxious and loud to his liking. "Now everybody say hey!" Present Mic was met with silence by the sitting crowd, but continued nonetheless. "What a refined response!" He yelled, getting another sigh from Kaneki.

 _Are all heroes like him?_ Kaneki thought with a frown.

"Anyways! I'll give you the rundown of how the practical exam will go!" He yelled with a finger up. "Are you ready?!" Met with silence once again, he answered the question himself. "Yeah!"

"Oh my gosh, it's the voice-type hero Present Mic…!" Kaneki heard someone whisper to themselves with excitement. He looked around and spotted the green-haired girl from earlier by the corner of his eyes. Her cheeks were bright red and she was covering her mouth with both hands in order to hide her big smile. "I listen to him on the radio every week, this is incredible. The lecturers at Yuuei are really pro heroes…!"

"Shut it." Came from the boy sitting beside Izuku. Kaneki shook his head briefly with a smile and returned his attention towards Present Mic.

"As it says in the application requirements, you listeners will be conducting ten-minute mock urban battles after this!" Present Mic said, as he moved his hands around with excitement. On the screen behind him, several things were displayed. "After the presentation, you'll head over to the designated area, okay?" Silence. "Okay?!"

Kaneki heard Izuku talk with the boy that told her to shut up, but decided to ignore them.

"We'll be sprinkling a large number of villains over the battlefield!" On the screen, they showed different shadows of robot-like figures, which were each assigned a certain amount of point to them. In the middle, a building area could be seen. "They'll appear in three different varieties with point values scaled accordingly to difficulty!"

"Your goal, dear listeners, is to rack up as many points as you can! Be it by using simply brute force or your quirks, it's up to you! As long as you immobilize the faux villains, you'll get points for it!" Present Mic said, pointing a finger at the sitting crowd with a grin. "Of course, attacking other examinees and any other unheroic actions are prohibited!" As he said so, he shook a slight finger at the crowd.

 _Tch… Unheroic, huh?_ Kaneki thought, his scowl deepening. _So in other words, I'm guessing that stealing a "kill" is prohibited as well. Well, there goes that plan._ Kaneki sighed and closed his eyes briefly.

"May I ask a question?" Said an examinee from the crowd.

"Ok!" Present Mic said. A light from above focused on the examinee and revealed a standing young teenager. He looked slightly older than the others, had short black hair that was swept to the side and wore glasses. His arm was raised highly.

"On the printout, there are four types of villains." The teenager pointed at the paper he held with his other hand. His eyes furrowed and he continued speaking loudly, too loudly for Kaneki's comfort. "If that is a misprint, then Yuuei, the most prominent school in Japan should be ashamed of such a foolish mistake!" He brought the paper down and held his hand close to his chest.

"We examinees are here in this place because we wish to be molded into exemplary heroes!" He then turned around and pointed at Izuku. "In addition, you there with the curly green hair -" Izuku pointed at herself in confusion, heat rising up to her cheeks as she got flustered. "You've been muttering this whole time. It's distracting. If you think this place is a pleasure joint then you should leave immediately!"

"I'm sorry!" Izuku yelped and covered her mouth, earning a few snickers and laughs from the others. Except for Kaneki, who was about to stand up.

"Okay, okay, examinee 711 and you examinee 143, sit down please!" Present Mic said, waving his hands in a motion that called for them to calm down.

Kaneki clicked his tongue and sat down as told, crossing his arms in the process. _Funny how a school for heroics would deny someone doing something that could be considered heroic..._ Kaneki thought, a frown forming on his lips and his eyes narrowing. _This is just one of the few reasons I'm siding with you, father._

"Thank you for the great message examinee 711!" Present Mic said with a grin and thumbs up. "Now, for the last type of villain. Surprise! It's worth 0 points!" He exclaimed, another shadow appearing on the screen that showed the new faux villain and it's points. "That guy's an obstacle, so to speak. There's one in every battle center, an obstacle that will go crazy in narrow spaces. It's impossible to defeat, but there's no reason to defeat it either. I recommend you listeners try to avoid it!"

"Thank you very much! Excuse the interruption!" Examinee 711 said, bowing to Present Mic before sitting on his seat.

"Alright, that's all from me! I'll give you guys a present - our school motto!" Present Mic explained, opening his arms wide. "The hero Napoleon Bonaparte once said: A true hero is someone who overcomes life's misfortunes. Go beyond. Plus Ultra!"

 _What a fake…_ Kaneki thought.

"Now, everyone, good luck suffering!"

* * *

The examinees were each driven by bus to their designated examination sites, after they were allowed to change. Kaneki currently stood in front of the examination's site gate that he was assigned to. According to the paper they were given, this was the examination site B, also called "Battle Center B". He whistled lightly at the sight in front of him. The site might as well have been a town.

Kaneki stood in front of the big gate and stretched out. He heard murmurs of a girl that was clumsy and whimpered a lot, thus the examinees deemed it lucky to have her as an opponent. Kaneki knew who they were talking about and simply sighed. He turned to look for the girl and found her talking with the boy that had called her out during the presentation. Kaneki stared at them in silence, as he debated about what he should do.

"Okay, start!" The voice came from above. Everyone turned their attention towards the voice and saw that Present Mic was yelling from the top of a watch tower. "What's wrong? There are no countdowns in real fights! Run! Run! The die has been cast you know!"

All for the lone green-haired girl, who was staring at Present Mic in confusement, had ran off into the sight. It didn't take long for Izuku to figure out that the others had ran off and she ran off herself. They kept running through the streets of the battle center, the crowd dispersing slowly as each head their different directions.

As Kaneki ran off on his own to the right, he saw a villain. As he dashed towards the faux villain, he punched it in the gut and sent it flying. His knuckles were severely damaged and were bleeding heavily, as his bones were broken. Despite the damage, he kept running and let his hand heal meanwhile.

As he and the other examinees battled the faux villains, the teachers examined carefully their talents behind screens.

"Doesn't this year's group look interesting?" A feminine voice said with interest.

"Well, we can't know for sure yet," A male voice said, excitement rising up in his rough voice. His finger neared a red button and he pressed it as he spoke a few words. "Their true test is yet to come."

 _Explosions?_ Kaneki thought, as he averted his gaze towards the loud sounds. Dust could be seen forming clouds and a huge figure emerged from the area. Looking over with slight interest, Kaneki kicked the head of the faux he stood on top of and headed over to the figure.

On his way through the streets, he saw examinees emerge from the dust clouds and flee in the opposite direction.

Kaneki cupped his chin and smiled, as he averted his gaze upwards and saw the huge faux villain wreck chaos.

 _So it's finally come, the self-sacrifice test…_ Kaneki thought, being aware of the purpose of the 0 point faux villain. _I wonder if I should take the time to defeat it and save those two girls…_ He stared at Izuku and the brown haired girl, who laid on the ground. _Hmm, no, I'm sure the teachers will rescue them before they get injured._ Kaneki turned around and moved his foot forward slowly, as he smiled happily. _Besides, I got enough points already._

As he walked, he heard Izuku stand up. He looked over his shoulder and saw Izuku running towards the faux villain. Kaneki's eyes widened and he nearly yelled after her.

 _Idiot! Why would she do that? Is she insane?!_ Kaneki thought, as he watched the green-haired girl dash towards the robot. He clicked his tongue and sped off after her. _Why am I even chasing her? Is it because she reminds me so much of myself?_ Kaneki thought, a scowl forming on his lips.

"Wait!" Kaneki shouted, but it was too late.

In front of him, he saw the girl jump high up in the air and pull her right arm back. His eyes widened, as he heard her yell.

"SMASH!"

The faux villain was beaten to a pulp with a single punch. A punch so strong that it caused a chain reaction of the robot's insides exploding. Kaneki's mouth was agape like the others, who watched in amazement at Izuku's feat.

Kaneki sped forwards, running as fast as he could to catch the fallen Izuku. He focused strength in his legs and jumped high up in the air, catching Izuku and landing in a crouched position. He stood up, as he held her bridal looked down at her and saw that she was crying.

"If I could only get one point…!" She spoke in a low voice, as her energy was drained and she fell unconscious. Kaneki saw her broken arm and legs, his eyes widening in shock.

 _A strength-enhancing quirk that damages the user's body, due to them being unable to control the quirk fully is common. But for it to be so strong and cause such backlash, it must be…_ Kaneki's fists clenched and he grit his teeth in anger, as he turned his back to the crowd so they couldn't see his expression. He furrowed his eyebrows and narrowed his eyes, glaring at the sleeping Izuku. As he did so, a crazed grin formed on his lips. _One for All._


End file.
